Untrusted Code ─( Syscall )─→ Host Kernel ─( Hardware API )─→ Hardware
The simplest approach is to check every single point. Compute the distance from the user's location to every restaurant in the database, keep the ones that are close enough, and throw away the rest.
，这一点在safew官方版本下载中也有详细论述
Police officers from Bangkok’s metropolitan bureau had less than 24 hours to prepare for their latest undercover operation. They would be starring as performers of a lion dance at a temple fair held for the lunar new year. Their mission: track down and arrest a suspected thief who had a history of evading officers.
我拿起她的小米手机，帮她设置了三道技术防线：第一，在设置里开启“禁止安装非官方应用来源”，从根本上杜绝了木马病毒的植入；第二，设置呼叫限制，拦截所有陌生号码的来电；第三，启用短信过滤，屏蔽非联系人发来的信息。